Abstract

Following traumatic brain injury catecholamines are routinely applied to increase cerebral perfusion. To date, it remains controversial if infusion of catecholamines is associated with diminished cerebral perfusion due to catecholamine-mediated vasoconstriction. The aims of the present study were to investigate the effects of norepinephrine and dopamine on cortical perfusion and brain edema following controlled cortical impact injury (CCII) in rats. Four hours after CCII, rats (n = 22) received either norepinephrine or dopamine with the aim of increasing MABP to 120 mm Hg for 90 minutes. Control rats were given NaCl. Cortical perfusion was measured before, during, and after catecholamine infusion using Laser Doppler flowmetry. Brain swelling was determined directly after the study period (8 hrs after CCII). Following CCII cortical perfusion was reduced by 40% compared to pre-trauma values in all rats. Parallel to the increases in MABP, cortical perfusion was significantly elevated under norepinephrine and dopamine, respectively (p < 0.05). Despite similar MABP values this increase was mostly sustained under norepinephrine. In control rats cortical perfusion remained diminished. Brain swelling was similar in all groups. Both norepinephrine and dopamine significantly increased cortical perfusion following CCII. Norepinephrine, however, was superior to dopamine in CBF. Based on increased CBF and unchanged brain swelling catecholamine-mediated vasoconstriction does not seem to occur under the present study design.

Abstract

Following traumatic brain injury catecholamines are routinely applied to increase cerebral perfusion. To date, it remains controversial if infusion of catecholamines is associated with diminished cerebral perfusion due to catecholamine-mediated vasoconstriction. The aims of the present study were to investigate the effects of norepinephrine and dopamine on cortical perfusion and brain edema following controlled cortical impact injury (CCII) in rats. Four hours after CCII, rats (n = 22) received either norepinephrine or dopamine with the aim of increasing MABP to 120 mm Hg for 90 minutes. Control rats were given NaCl. Cortical perfusion was measured before, during, and after catecholamine infusion using Laser Doppler flowmetry. Brain swelling was determined directly after the study period (8 hrs after CCII). Following CCII cortical perfusion was reduced by 40% compared to pre-trauma values in all rats. Parallel to the increases in MABP, cortical perfusion was significantly elevated under norepinephrine and dopamine, respectively (p < 0.05). Despite similar MABP values this increase was mostly sustained under norepinephrine. In control rats cortical perfusion remained diminished. Brain swelling was similar in all groups. Both norepinephrine and dopamine significantly increased cortical perfusion following CCII. Norepinephrine, however, was superior to dopamine in CBF. Based on increased CBF and unchanged brain swelling catecholamine-mediated vasoconstriction does not seem to occur under the present study design.

Download

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.